Connectable and disconnectable couplings are available in many different types and in large numbers. The purpose of the couplings is to produce connections, for example hydraulic connections, in power transmission, supply and similar equipment. Various ways are known in the art for arranging the coupling components with protective sleeves which prevent the penetration of dirt, impurities and foreign particles to the inside of the coupling components. Also previously known in the art is the arrangement in which the coupling components are connected in various ways, for example in order to provide a quick connection function, using mechanical or hydraulic coupling accessories, etc.